use hardware occlusion query for sun glare effect

apps/openmw/mwrender/occlusionquery.cpp

@@ -2,13 +2,17 @@
 
 #include <OgreRenderSystem.h>
 #include <OgreRoot.h>
+#include <OgreBillboardSet.h>
 
 using namespace MWRender;
 using namespace Ogre;
 
-OcclusionQuery::OcclusionQuery() :
+OcclusionQuery::OcclusionQuery(OEngine::Render::OgreRenderer* renderer, SceneNode* sunNode) :
-    mSunTotalAreaQuery(0), mSunVisibleAreaQuery(0)
+    mSunTotalAreaQuery(0), mSunVisibleAreaQuery(0), mActiveQuery(0), mDoQuery(0), mSunVisibility(0)
 {
+    mRendering = renderer;
+    mSunNode = sunNode;
+
     try {
         RenderSystem* renderSystem = Root::getSingleton().getRenderSystem();
 
@@ -23,5 +27,113 @@ OcclusionQuery::OcclusionQuery() :
     }
 
     if (!mSupported)
+    {
         std::cout << "Hardware occlusion queries not supported." << std::endl;
+        return;
+    }
+
+    // This means that everything up to RENDER_QUEUE_MAIN can occlude the objects that are tested
+    const int queue = RENDER_QUEUE_MAIN+1;
+
+    MaterialPtr matBase = MaterialManager::getSingleton().getByName("BaseWhiteNoLighting");
+    MaterialPtr matQueryArea = matBase->clone("QueryTotalPixels");
+    matQueryArea->setDepthWriteEnabled(false);
+    matQueryArea->setColourWriteEnabled(false);
+    matQueryArea->setDepthCheckEnabled(false); // Not occluded by objects
+    MaterialPtr matQueryVisible = matBase->clone("QueryVisiblePixels");
+    matQueryVisible->setDepthWriteEnabled(false);
+    matQueryVisible->setColourWriteEnabled(false);
+    matQueryVisible->setDepthCheckEnabled(true); // Occluded by objects
+
+    mBBQueryTotal = mRendering->getScene()->createBillboardSet(1);
+    mBBQueryTotal->setDefaultDimensions(150, 150);
+    mBBQueryTotal->createBillboard(Vector3::ZERO);
+    mBBQueryTotal->setMaterialName("QueryTotalPixels");
+    mBBQueryTotal->setRenderQueueGroup(queue);
+    mSunNode->attachObject(mBBQueryTotal);
+
+    mBBQueryVisible = mRendering->getScene()->createBillboardSet(1);
+    mBBQueryVisible->setDefaultDimensions(150, 150);
+    mBBQueryVisible->createBillboard(Vector3::ZERO);
+    mBBQueryVisible->setMaterialName("QueryVisiblePixels");
+    mBBQueryVisible->setRenderQueueGroup(queue);
+    mSunNode->attachObject(mBBQueryVisible);
+
+    mRendering->getScene()->addRenderObjectListener(this);
+    mDoQuery = true;
 }
+
+OcclusionQuery::~OcclusionQuery()
+{
+    RenderSystem* renderSystem = Root::getSingleton().getRenderSystem();
+    if (mSunTotalAreaQuery) renderSystem->destroyHardwareOcclusionQuery(mSunTotalAreaQuery);
+    if (mSunVisibleAreaQuery) renderSystem->destroyHardwareOcclusionQuery(mSunVisibleAreaQuery);
+}
+
+bool OcclusionQuery::supported()
+{
+    return mSupported;
+}
+
+void OcclusionQuery::notifyRenderSingleObject(Renderable* rend, const Pass* pass, const AutoParamDataSource* source, 
+			const LightList* pLightList, bool suppressRenderStateChanges)
+{
+    if (!mSupported) return;
+
+    // The following code activates and deactivates the occlusion queries
+    // so that the queries only include the rendering of their intended targets
+
+    // Close the last occlusion query
+    // Each occlusion query should only last a single rendering
+    if (mActiveQuery != NULL)
+    {
+        mActiveQuery->endOcclusionQuery();
+        mActiveQuery = NULL;
+    }
+
+    // Open a new occlusion query
+    if (mDoQuery == true)
+    {
+        if (rend == mBBQueryTotal) 
+            mActiveQuery = mSunTotalAreaQuery;
+        else if (rend == mBBQueryVisible) 
+            mActiveQuery = mSunVisibleAreaQuery;
+
+        if (mActiveQuery != NULL)
+        {
+            mActiveQuery->beginOcclusionQuery();
+        }
+    }
+}
+
+void OcclusionQuery::update()
+{
+    if (!mSupported) return;
+
+    // Stop occlusion queries until we get their information
+    // (may not happen on the same frame they are requested in)
+    mDoQuery = false;
+
+    if (!mSunTotalAreaQuery->isStillOutstanding() && !mSunVisibleAreaQuery->isStillOutstanding())
+    {
+        unsigned int totalPixels;
+        unsigned int visiblePixels;
+
+        mSunTotalAreaQuery->pullOcclusionQuery(&totalPixels);
+        mSunVisibleAreaQuery->pullOcclusionQuery(&visiblePixels);
+
+        if (totalPixels == 0)
+        {
+            // probably outside of the view frustum
+            mSunVisibility = 0;
+        }
+        else
+        {
+            mSunVisibility = float(visiblePixels) / float(totalPixels);
+            if (mSunVisibility > 1) mSunVisibility = 1;
+        }
+
+        mDoQuery = true;
+    }
+}
+

apps/openmw/mwrender/occlusionquery.hpp

@@ -2,25 +2,49 @@
 #define _GAME_OCCLUSION_QUERY_H
 
 #include <OgreHardwareOcclusionQuery.h>
+#include <OgreRenderObjectListener.h>
+
+#include <openengine/ogre/renderer.hpp>
 
 namespace MWRender
 {
     ///
     /// \brief Implements hardware occlusion queries on the GPU
     ///
-    class OcclusionQuery
+    class OcclusionQuery : public Ogre::RenderObjectListener
     {
     public:
-        OcclusionQuery();
+        OcclusionQuery(OEngine::Render::OgreRenderer*, Ogre::SceneNode* sunNode);
+        ~OcclusionQuery();
 
         bool supported();
         ///< returns true if occlusion queries are supported on the user's hardware
 
+        void update();
+        ///< per-frame update
+
+        float getSunVisibility() const {return mSunVisibility;};
+
     private:
         Ogre::HardwareOcclusionQuery* mSunTotalAreaQuery;
         Ogre::HardwareOcclusionQuery* mSunVisibleAreaQuery;
+        Ogre::HardwareOcclusionQuery* mActiveQuery;
+
+        Ogre::BillboardSet* mBBQueryVisible;
+        Ogre::BillboardSet* mBBQueryTotal;
+
+        Ogre::SceneNode* mSunNode;
+
+        float mSunVisibility;
 
         bool mSupported;
+        bool mDoQuery;
+
+        OEngine::Render::OgreRenderer* mRendering;
+
+    protected:
+        virtual void notifyRenderSingleObject(Ogre::Renderable* rend, const Ogre::Pass* pass, const Ogre::AutoParamDataSource* source, 
+			const Ogre::LightList* pLightList, bool suppressRenderStateChanges);
     };
 }
 

apps/openmw/mwrender/renderingmanager.cpp

@@ -55,11 +55,11 @@ RenderingManager::RenderingManager (OEngine::Render::OgreRenderer& _rend, const
     Ogre::SceneNode *cameraPitchNode = cameraYawNode->createChildSceneNode();
     cameraPitchNode->attachObject(mRendering.getCamera());
     
-    mOcclusionQuery = new OcclusionQuery();
-    
     //mSkyManager = 0;
     mSkyManager = new SkyManager(mMwRoot, mRendering.getCamera(), &environment);
 
+    mOcclusionQuery = new OcclusionQuery(&mRendering, mSkyManager->getSunNode());
+
     mPlayer = new MWRender::Player (mRendering.getCamera(), playerNode);
     mSun = 0;
 
@@ -150,8 +150,12 @@ void RenderingManager::update (float duration){
 
     mActors.update (duration);
 
+    mOcclusionQuery->update();
+
     mSkyManager->update(duration);
 
+    mSkyManager->setGlare(mOcclusionQuery->getSunVisibility());
+
     mRendering.update(duration);
 
     mLocalMap->updatePlayer( mRendering.getCamera()->getRealPosition(), mRendering.getCamera()->getRealDirection() );

apps/openmw/mwrender/renderingmanager.hpp

@@ -99,6 +99,8 @@ class RenderingManager: private RenderingInterface {
     void sunEnable();
     void sunDisable();
 
+    bool occlusionQuerySupported() { return mOcclusionQuery->supported(); };
+
     void setGlare(bool glare);
     void skyEnable ();
     void skyDisable ();

apps/openmw/mwrender/sky.cpp

@@ -12,6 +12,7 @@
 
 #include "../mwworld/environment.hpp"
 #include "../mwworld/world.hpp"
+#include "occlusionquery.hpp"
 
 using namespace MWRender;
 using namespace Ogre;
@@ -30,7 +31,7 @@ BillboardObject::BillboardObject()
 
 void BillboardObject::setVisible(const bool visible)
 {
-    mNode->setVisible(visible);
+    mBBSet->setVisible(visible);
 }
 
 void BillboardObject::setSize(const float size)
@@ -88,7 +89,7 @@ void BillboardObject::init(const String& textureName,
     /// \todo These billboards are not 100% correct, might want to revisit them later
     mBBSet = sceneMgr->createBillboardSet("SkyBillboardSet"+StringConverter::toString(bodyCount), 1);
     mBBSet->setDefaultDimensions(550.f*initialSize, 550.f*initialSize);
-    mBBSet->setRenderQueueGroup(RENDER_QUEUE_SKIES_EARLY+2);
+    mBBSet->setRenderQueueGroup(RENDER_QUEUE_MAIN+2);
     mBBSet->setBillboardType(BBT_PERPENDICULAR_COMMON);
     mBBSet->setCommonDirection( -position.normalisedCopy() );
     mNode = rootNode->createChildSceneNode();
@@ -293,7 +294,7 @@ void SkyManager::ModVertexAlpha(Entity* ent, unsigned int meshType)
 }
 
 SkyManager::SkyManager (SceneNode* pMwRoot, Camera* pCamera, MWWorld::Environment* env) :
-    mGlareFade(0), mGlareEnabled(false)
+    mGlare(0), mGlareFade(0)
 {
     mEnvironment = env;
     mViewport = pCamera->getViewport();
@@ -562,10 +563,23 @@ void SkyManager::update(float duration)
     mMasser->setPhase( static_cast<Moon::Phase>( (int) ((mDay % 32)/4.f)) );
     mSecunda->setPhase ( static_cast<Moon::Phase>( (int) ((mDay % 32)/4.f)) );
 
-    // increase the strength of the sun glare effect depending
+
-    // on how directly the player is looking at the sun
     if (mSunEnabled)
     {
+        // take 1/5 sec for fading the glare effect from invisible to full
+        if (mGlareFade > mGlare)
+        {
+            mGlareFade -= duration*5;
+            if (mGlareFade < mGlare) mGlareFade = mGlare;
+        }
+        else if (mGlareFade < mGlare)
+        {
+            mGlareFade += duration*5;
+            if (mGlareFade > mGlare) mGlareFade = mGlare;
+        }
+
+        // increase the strength of the sun glare effect depending
+        // on how directly the player is looking at the sun
         Vector3 sun = mSunGlare->getPosition();
         sun = Vector3(sun.x, sun.z, -sun.y);
         Vector3 cam = mViewport->getCamera()->getRealDirection();
@@ -573,21 +587,10 @@ void SkyManager::update(float duration)
         float val = 1- (angle.valueDegrees() / 180.f);
         val = (val*val*val*val)*2;
 
-        if (mGlareEnabled)
+        mSunGlare->setSize(val * mGlareFade);
-        {
-            mGlareFade += duration*3;
-            if (mGlareFade > 1) mGlareFade = 1;
-        }
-        else
-        {
-            mGlareFade -= duration*3;
-            if (mGlareFade < 0.3) mGlareFade = 0;
-        }
-
-        mSunGlare->setSize(val * (mGlareFade));
     }
 
-    mSunGlare->setVisible(mGlareFade>0 && mSunEnabled);
+    mSunGlare->setVisible(mSunEnabled);
     mSun->setVisible(mSunEnabled);
     mMasser->setVisible(mMasserEnabled);
     mSecunda->setVisible(mSecundaEnabled);
@@ -689,15 +692,15 @@ void SkyManager::setWeather(const MWWorld::WeatherResult& weather)
     else
         strength = 1.f;
 
-    mSunGlare->setVisibility(weather.mGlareView * strength);
+    mSunGlare->setVisibility(weather.mGlareView * mGlareFade * strength);
-    mSun->setVisibility(strength);
+    mSun->setVisibility(mGlareFade >= 0.5 ? weather.mGlareView * mGlareFade * strength : 0);
 
     mAtmosphereNight->setVisible(weather.mNight && mEnabled);
 }
 
-void SkyManager::setGlare(bool glare)
+void SkyManager::setGlare(const float glare)
 {
-    mGlareEnabled = glare;
+    mGlare = glare;
 }
 
 Vector3 SkyManager::getRealSunPos()
@@ -782,3 +785,8 @@ void SkyManager::setDate(int day, int month)
     mDay = day;
     mMonth = month;
 }
+
+Ogre::SceneNode* SkyManager::getSunNode()
+{
+    return mSun->getNode();
+}

apps/openmw/mwrender/sky.hpp

@@ -138,6 +138,8 @@ namespace MWRender
 
         void setWeather(const MWWorld::WeatherResult& weather);
 
+        Ogre::SceneNode* getSunNode();
+
         void sunEnable();
 
         void sunDisable();
@@ -160,7 +162,7 @@ namespace MWRender
 
         void setThunder(const float factor);
 
-        void setGlare(bool glare);
+        void setGlare(const float glare);
         Ogre::Vector3 getRealSunPos();
         
     private:
@@ -203,12 +205,12 @@ namespace MWRender
                 
         float mRemainingTransitionTime;
         
-        float mGlareFade;
+        float mGlare; // target
+        float mGlareFade; // actual
         
         void ModVertexAlpha(Ogre::Entity* ent, unsigned int meshType);
         
         bool mEnabled;
-        bool mGlareEnabled;
         bool mSunEnabled;
         bool mMasserEnabled;
         bool mSecundaEnabled;

apps/openmw/mwworld/world.cpp

@@ -705,13 +705,16 @@ namespace MWWorld
 
         mWeatherManager->update (duration);
 
-        // cast a ray from player to sun to detect if the sun is visible
+        if (!mRendering->occlusionQuerySupported())
-        // this is temporary until we find a better place to put this code
+        {
-        // currently its here because we need to access the physics system
+            // cast a ray from player to sun to detect if the sun is visible
-        float* p = mPlayer->getPlayer().getRefData().getPosition().pos;
+            // this is temporary until we find a better place to put this code
-        Vector3 sun = mRendering->getSkyManager()->getRealSunPos();
+            // currently its here because we need to access the physics system
-        sun = Vector3(sun.x, -sun.z, sun.y);
+            float* p = mPlayer->getPlayer().getRefData().getPosition().pos;
-        mRendering->getSkyManager()->setGlare(!mPhysics->castRay(Ogre::Vector3(p[0], p[1], p[2]), sun));
+            Vector3 sun = mRendering->getSkyManager()->getRealSunPos();
+            sun = Vector3(sun.x, -sun.z, sun.y);
+            mRendering->getSkyManager()->setGlare(!mPhysics->castRay(Ogre::Vector3(p[0], p[1], p[2]), sun));
+        }
     }
 
     bool World::isCellExterior() const